990 resultados para Anti-GITR (DTA-1)


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Ischemia reperfusion injury (IRI) is a potential contributor for the development of chronic allograft nephropathy. T cells are important mediators of injury, even in the absence of alloantigens. We performed a depletion of TCD4(+)CTLA4(+)Foxp3(+) cells with anti-CD25(PC61), a treatment with anti-GITR (DTA-1) and rat-IgG, followed by 45 min of ischemia and 24/72 h of reperfusion, and then analyzed blood urea, kidney histopathology and gene expression in kidneys by QReal Time PCR. After 24 h of reperfusion, depletion of TCD4(+)CTLA4(+)Foxp3(+) cells reached 30.3%(spleen) and 67.8%(lymph nodes). 72 h after reperfusion depletion reached 43.1%(spleen) and 90.22%(lymph nodes) and depleted animals presented with significantly poorer renal function, while DTA-1 (anti-GITR)-treated ones showed a significant protection, all compared to serum urea from control group (IgG: 150.10 +/- 50.04; PC61: 187.23 +/- 31.38; DTA-1: 64.53 +/- 25.65, mg/dL, p<0.05). These data were corroborated by histopathology. We observed an increase of HO-1 expression in animals treated with DTA-1 at 72 h of reperfusion with significant differences. Thus, our results suggest that PC61 (anti-CD25) mAb treatment is deleterious, while DTA-1 (anti-GITR) mAb treatment presents a protective role in the renal IRI, indicating that some regulatory populations of T cells might have a role in IRI. (C) 2009 Elsevier B.V. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Background. The mechanisms underlying pleural inflammation and pleurodesis are poorly understood. We hypothesized that the cytokines transforming growth factor beta (TGF beta 1) and vascular endothelial growth factor (VEGF) play a major role in pleurodesis after intrapleural silver nitrate (SN) injection. Method. Forty rabbits received intrapleurally 0.5% SN alone or 0.5% SN + anti-TGF beta 1, anti-IL-8, or anti-VEGF. After 28 days, the animals were euthanized and macroscopic pleural adhesions, microscopic pleural fibrosis, and collagen deposition were analyzed for characterization of the degree of pleurodesis (scores 0-4). Results. Scores of pleural adhesions, pleural fibrosis, total collagen, and thin collagen fibers deposition after 28 days were significantly lower for 0.5% SN + anti-TGF beta 1 and 0.5% SN + anti-VEGF. Significant correlations were found between macroscopic adhesion and microscopic pleural fibrosis with total collagen and thin collagen fibers. Conclusions. We conclude that both TGF beta 1 and VEGF, but not IL-8, mediate the pleural inflammatory response and pleurodesis induced by SN.

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Anti-silencing factor 1 (ASF1) is a histone chaperone that contributes to the histone deposition during nucleosome assembly in newly replicated DNA. It is involved in chromatin disassembly, transcription activation and in the cellular response to DNA damage. In Leishmania major the ASF1 gene (LmASF1) is located in chromosome 20 and codes for a protein showing 67% of identity with the Trypanosoma brucei TbASF1a. Compared to orthologous proteins, LmASF1 conserves the main residues relevant for its various biological functions. To study ASF1 in Leishmania we generated a mutant overexpressing LmASF1 in L. major. We observed that the excess of LmASF1 impaired promastigotes growth rates and had no impact on cell cycle progress. Differently from yeast, ASF1 overproduction in Leishmania did not affect expression levels of genes located on telomeres, but led to an upregulation of proteins involved in chromatin remodelling and physiological stress, such as heat shock proteins, oxidoreductase activity and proteolysis. In addition, we observed that LmASF1 mutant is more susceptible to the DNA damaging agent, methyl methane sulphonate, than the control line. Therefore, our study suggests that ASF1 from Leishmania pertains to the chromatin remodelling machinery of the parasite and acts on its response to DNA damage.

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BACKGROUND: Natural xenoreactive antibodies (Abs) directed against the Bdi-epitope (Gal alpha 1-3Gal beta) on the cells of non-primate mammals take part in hyperacute rejection of xenotransplanted organs. We found that some Abs, which were one-step affinity purified on Bdi-Sepharose, cross-reacted with the disaccharide Gal alpha 1-4GlcNAc beta. The epitope Gal alpha 1-4GlcNAc has not been identified on mammals or bacterial polysaccharides yet. METHODS: To isolate the antibodies of the corresponding specificity the disaccharide was immobilized on Sepharose and antibodies were affinity purified from pooled serum of blood group O individuals. RESULTS: These one-step purified Abs cross-reacted with Bdi, but after a prior absorption step on Bdi-Sepharose no cross-reactivity with Bdi was observed any longer. Surprisingly, the quantity of anti-Gal alpha 1-4GlcNAc isolated from the same serum pool, 4-7 microg/ml, was equal to that of anti-Bdi or more. Independently of ABO blood groups all the tested healthy donors had anti-Gal alpha 1-4GlcNAc Abs at a similar level. Monospecific anti-Gal alpha 1-4GlcNAc Abs were not cytotoxic towards porcine cells. CONCLUSIONS: 1. The actual concentration of monospecific, xenoreactive Gal alpha 1-3Gal beta Abs in blood may be considerably lower than the value referred to in the literature for 'anti-alpha Gal' or 'anti-Galili' antibodies. 2. Anti-Gal alpha 1-4GlcNAc Abs seem not to be important for xenotransplantation.

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Lifshitz space–times with critical exponent z = 2 can be obtained by dimensional reduction of Schrödinger space–times with critical exponent z = 0. The latter space–times are asymptotically anti-de Sitter (AdS) solutions of AdS gravity coupled to an axion–dilaton system (or even just a massless scalar field). This basic observation is used to perform holographic renormalization for four-dimensional asymptotically locally Lifshitz space–times by dimensional reduction of the corresponding problem of holographic renormalization for five-dimensional asymptotically AdS space–times coupled to an axion–dilaton system. In this setup the four-dimensional structure of the Lifshitz – Fefferman-Graham expansion and the structure of the counterterm action, including the scale anomaly, will be summarized.

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BACKGROUND AND AIMS: Naturally occurring anti-idiotypic antibodies structurally mimic the original antibody epitope. Anti-idiotypes, therefore, are interesting tools for the portrayal of conformational B-cell epitopes of allergens. In this study we used this strategy particularly for major timothy grass pollen (Phleum pratense) allergen Phl p 1. METHODS AND RESULTS: We used a combinatorial phage display library constructed from the peripheral IgG repertoire of a grass pollen allergic patient which was supposed to contain anti-idiotypic Fab specificities. Using purified anti-Phl p 1 IgG for biopanning, several Fab displaying phage clones could be isolated. 100 amplified colonies were screened for their binding capacity to anti-Phl p 1-specific antibodies, finally resulting in four distinct Fab clones according to sequence analysis. Interestingly, heavy chains of all clones derived from the same germ line sequence and showed high homology in their CDRs. Projecting their sequence information on the surface of the natural allergen Phl p 1 (PDB ID: 1N10) indicated matches on the N-terminal domain of the homo-dimeric allergen, including the bridging region between the two monomers. The resulting epitope patches were formed by spatially distant sections of the primary allergen sequence. CONCLUSION: In this study we report that anti-idiotypic specificities towards anti-Phl p 1 IgG, selected from a Fab library of a grass pollen allergic patient, mimic a conformational epitope patch being distinct from a previously reported IgE epitope area.

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Background and purpose of the study: Herbal enhancers compared to the synthetic ones have shown less toxis effects. Coumarins have been shown at concentrations inhibiting phospoliphase C-Y (Phc-Y) are able to enhance tight junction (TJ) permeability due to hyperpoalation of Zonolous Occludense-1 (ZO-1) proteins. The purpose of this study was to evaluate the influence of ethanolic extract of Angelica archengelica (AA-E) which contain coumarin on permeation of repaglinide across rat epidermis and on the tight junction plaque protein ZO-1 in HaCaT cells. Methods: Transepidermal water loss (TEWL) from the rat skin treated with different concentrations of AA-E was assessed by Tewameter. Scanning and Transmission Electron Microscopy (TEM) on were performed on AA-E treated rat skin portions. The possibility of AA-E influence on the architecture of tight junctions by adverse effect on the cytoplasmic ZO-1 in HaCaT cells was investigated. Finally, the systemic delivery of repaglinide from the optimized transdermal formulation was investigated in rats. Results: The permeation of repaglinide across excised rat epidermis was 7-fold higher in the presence of AA-E (5% w/v) as compared to propylene glycol:ethanol (7:3) mixture. The extract was found to perturb the lipid microconstituents in both excised and viable rat skin, although, the effect was less intense in the later. The enhanced permeation of repaglinide across rat epidermis excised after treatment with AA-E (5% w/v) for different periods was in concordance with the high TEWL values of similarly treated viable rat skin. Further, the observed increase in intercellular space, disordering of lipid structure and corneocyte detachment indicated considerable effect on the ultrastructure of rat epidermis. Treatment of HaCaT cell line with AA-E (0.16% w/v) for 6 hrs influenced ZO-1 as evidenced by reduced immunofluorescence of anti-TJP1 (ZO-1) antibody in Confocal Laser Scanning Microscopy studies (CLSM) studies. The plasma concentration of repaglinide from transdermal formulation was maintained higher and for longer time as compared to oral administration of repaglinide. Major conclusion: Results suggest the overwhelming influence of Angelica archengelica in enhancing the percutaneous permeation of repaglinide to be mediated through perturbation of skin lipids and tight junction protein (ZO-1).

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We described herein the molecular design of novel in vivo anti-inflammatory 6-methanesulfonamide-3,4-methylenedioxyphenyl-N-acylhydrazone derivatives (1) planned by applying the molecular hybridization approach. This work also points out to the discovery of LASSBio-930 (1c) as a novel anti-inflammatory and anti-hyperalgesic prototype, which was able to reduce carrageenan-induced rat paw edema with an ED(50) of 97.8 mu mol/kg, acting mainly as a non-selective COX inhibitor. (C) 2009 Elsevier Ltd. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)